问题
I need to download large .zip files (up to 800 MB) with my iPad app. I want to resume the download again if it is canceled or if the app is in the background.
operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
operation.outputStream = [NSOutputStream outputStreamToFileAtPath:filePath append:YES];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject){
// unzip the .zip
}failure:^(AFHTTPRequestOperation *operation, NSError *error){
//Handle the error
}];
[operation setDownloadProgressBlock:^(NSInteger bytesWritten, long long totalBytesWritten,long long totalBytesExpectedToWrite) {
//update the progressView
}];
[operation setShouldExecuteAsBackgroundTaskWithExpirationHandler:^{
// What I have to do here?
}];
[operation start];
[operation waitUntilFinished];
-(void)applicationWillResignActive:(UIApplication *)application{
// What I have to do here?
}
Thanks for your help.
回答1:
You can use AFDownloadRequestOperation to do this.
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"....zip"]];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *path = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"....zip"];
AFDownloadRequestOperation *operation = [[AFDownloadRequestOperation alloc] initWithRequest:request targetPath:path shouldResume:YES];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(@"Successfully downloaded file to %@", path);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(@"Error: %@", error);
}];
[operation setProgressiveDownloadProgressBlock:^(NSInteger bytesRead, long long totalBytesRead, long long totalBytesExpected, long long totalBytesReadForFile, long long totalBytesExpectedToReadForFile) {
NSLog(@"Operation%i: bytesRead: %d", 1, bytesRead);
NSLog(@"Operation%i: totalBytesRead: %lld", 1, totalBytesRead);
NSLog(@"Operation%i: totalBytesExpected: %lld", 1, totalBytesExpected);
NSLog(@"Operation%i: totalBytesReadForFile: %lld", 1, totalBytesReadForFile);
NSLog(@"Operation%i: totalBytesExpectedToReadForFile: %lld", 1, totalBytesExpectedToReadForFile);
}];
[operations addObject:operation];
After you restart your app, and generate the request having a same url, it will resume downloading. "shouldResume:YES" works
来源：https://stackoverflow.com/questions/12173744/afnetworking-pause-resume-downloading-big-files